• Nuclear Engineering and Technology
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• 제52권3호
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• pp.654-659
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• 2020

The reliability of the spent fuel pool instrument is very important for the security of nuclear power plant, especially during the earthquake. The effect of the fluid force on the vibration characteristics of the flexible tube of the spent fuel pool instrument needs comprehensive analysis. In this paper, based on the potential flow theory, the hydrodynamic pressures acting on the flexible tube were obtained. A mathematical model of a flexible tube was constructed to obtain the dynamic response considering the effects of seismic load and fluid force, and a computer code was written. Based on the mathematical model and computer code, the maximum stresses of the flexible tube in both safe shutdown earthquake and operating basis earthquake events on the spent fuel pool with three typical water levels were calculated, respectively. The results show that the fluid force has an obvious effect on the stress and strain of the flexible tube in both safe shutdown earthquake and operating basis earthquake events.

• 한국지진공학회논문집
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• 제3권1호
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• pp.29-40
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• 1999

주거용 건축물은 구조적 측면에서 고려해야할 많은 문제점을 안고 있다. 특히 건물이 고층화 될수록 동적인 특성으로 인해 바람 또는 지진과 같은 황하중의 영향애 커진다. 풍하중과는 달리 지진하중은 비슷한 구조물일지라도 동적특성에 의해 결정되고 예측이어렵다. 본 연구의 목적은 지진 발생이 아파트 옥탑층 물탱크가 건물의 거동에 미치는 영향을 파악하는 것이다. 옥탑층 물탱크가 건물의 거동에 미치는 영향을 파악하기 위하여 옥탑층 물탱크를 고려한 경우와 고려하지 않은 경우에 대하여 동적해석을 수행하였다 또한 옥탑층 물탱크가 구조부재에 미치는 영향을 파악하기 위하여 아파트 건물의 구조설계를 수행하였으며 지진하중의 영향을 평가하기 위하여 최대지진가속도를 변화시키면서 구조설계를 수행하였다 옥탑층 물탱크가 건물의 전체적인 거동에는 많은 큰 영향을 미친 것으로 나타났으나 각 부재의 설계에는 영향을 미치지 않았으며 0.4g의 최대지진가속도에서 일부 부재가 영향을 받는 것으로 나타났다.

• Earthquakes and Structures
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• 제12권5호
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• pp.529-541
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• 2017

According to the definition, progressive collapse could occur due to the initial partial failure of the structural members which by spreading to the adjacent members, could result in partial or overall collapse of the structure. Up to now, most researchers have investigated the progressive collapse due to explosion, fire or impact loads. But new research has shown that the seismic load could also be a factor for initiation of the progressive collapse. In this research, the progressive collapse capacity for the 5 and 15-story steel special moment resisting frames using push-down nonlinear static analysis, and nonlinear dynamic analysis under the gravity loads specified in the GSA Guidelines, were studied. After identifying the critical members, in order to investigate the seismic progressive collapse, the 5-story steel special moment resisting frame was analyzed by the nonlinear time history analysis under the effect of earthquakes with different characteristics. In order to account for the initial damage, one of the critical columns was weakened at the initiation of the earthquake or its Peak Ground Acceleration (PGA). The results of progressive collapse analyses showed that the potential of progressive collapse is considerably dependent upon location of the removed column and the number of stories, also the results of seismic progressive collapse showed that the dynamic response of column removal under the seismic load is completely dependent on earthquake characteristics like Arias intensity, PGA and earthquake frequency contents.

• 한국지진공학회논문집
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• 제19권5호
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• pp.247-256
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• 2015

This paper briefly introduces the design seismic loads in Korea (KBC 2009). Then, over 10,000 recorded earthquake ground accelerograms, with their magnitude ranging from 4.0 to 8.0 and their epicentral distance ranging from 0 to 200 km, were used to examine the appropriateness of seismic load defined in Korea known as a low-to-moderate seismicity region. The following conclusions are drawn based on the results: (1) The effective peak ground accelerations (EPA) of recorded earthquake accelerograms under $M{\leq}6.0$ and $R{\geq}15km$ appear to be less than that of MCE in Korea for all site conditions defined in KBC 2009. (2) The design spectrum (two-thirds of the intensity of MCE) in KBC 2009 is comparable to those of earthquake records in the magnitude 6 - 7 and the epicentral distance less than 50 km. Therefore, (3) the intensity of Korean design earthquake is considered to be overly high since the Korea peninsula is generally conceived to be a low-seismicity region.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2003년도 춘계 학술발표회논문집
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• pp.409-414
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• 2003

A multi-span bridge model that is fixed in longitudinal direction at a single pier can be very vulnerable to the earthquake ground motion in longitudinal direction. If the seismic load exceeds the capacity of the pier, it can be severely damaged. However, such incident can be prevented if piers of movable support share the seismic load as setting up seismic load transmitting device. This study is performed to investigate seismic performance of continuous bridge model with seismic load transmitting devices which is proposed newly. It is found that continuous bridge model system with device is more effective about displacement control and seismic performance.

• 한국지진공학회논문집
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• 제27권3호
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• pp.139-145
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• 2023

It is essential to determine a proper earthquake time history as a seismic load in a seismic design for a critical structure. In the code, a seismic load should satisfy a design response spectrum and include the characteristic of a target fault. The characteristic of a fault can be represented by a definition of a type of possible earthquake time history shape that occurred in a target fault. In this paper, the pseudo-basis function is proposed to be used to construct a specific type of earthquake, including the characteristic of a target fault. The pseudo-basis function is derived from analyzing the earthquake time history of specific fault harmonic wavelet transform. To show the feasibility of this method, the proposed method was applied to the faults causing the Gyeong-Ju ML5.8 and Pohang ML5.3 earthquakes.

• 한국지진공학회논문집
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• 제8권2호
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• pp.73-81
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• 2004

본 연구에서는 기존 철근콘크리트건물 보-기둥 접합부의 내진 성능을 개선하기 위하여 탄소섬유를 사용하여 구조물을 보강한 후 실험을 수행하였다. 이를 위하여 6개의 철근콘크리트 보-기둥 접합부를 제작하였으며, 지진하중과 같은 반복하중이 작용할 때 보강재료 및 보강영역 등을 변수로 하여 실험을 수행하여 각 보강변수에 따른 보강효과를 평가하였다. 본 실험을 통하여 구조물의 내진 성능 및 연성능력을 증진시킬 목적으로 새로운 보강재료(탄소섬유판, 탄소섬유봉, 탄소섬유쉬트)로 설계된 보강 실험체(RPC-CP2, RPC-CR, RJC-CP, RJC-CR)들은 내력증진은 물론이고 안정적인 이력거동을 확보할 수 있었다.

• Steel and Composite Structures
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• 제3권3호
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• pp.185-198
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• 2003

The concept of performance based seismic design has been gradually accepted by the earthquake engineering profession recently, in which the cost-effectiveness criterion is one of the most important principles and more attention is paid to the structural performance at the inelastic stage. Since there are many uncertainties in seismic design, reliability analysis is a major task in performance based seismic design. However, structural reliability analysis may be very costly and time consuming because the limit state function is usually a highly nonlinear implicit function with respect to the basic design variables, especially for the complex large-scale structures for dynamic and nonlinear analysis. Understanding statistical properties of the structural inelastic deformation, which is the aim of the present paper, is helpful to develop an efficient approximate approach of reliability analysis. The present paper studies the statistical properties of the maximum elastoplastic story drift of steel frames subjected to earthquake load. The randomness of earthquake load, dead load, live load, steel elastic modulus, yield strength and structural member dimensions are considered. Possible probability distributions for the maximum story are evaluated using K-S test. The results show that the choice of the probability distribution for the maximum elastoplastic story drift of steel frames is related to the mean value of the maximum elastoplastic story drift. When the mean drift is small (less than 0.3%), an extreme value type I distribution is the best choice. However, for large drifts (more than 0.35%), an extreme value type II distribution is best.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 춘계학술대회논문집
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• pp.1210-1215
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• 2002

The spent fuel handling tool is used to handle the refuel bundle and treated by hoist rope on the bridge crane. The new developed handling tool of NPP(Nuclear Power Plant) should be conformed the structural stability under earthquake condition. In this study, the stress and seismic analysis of the handling tool are performed by finite element method. Using the Floor Response Spectrum(FRS) obtained through the time history analysis, the modal and seismic analysis under Operating Basis Earthquake(OBE) and Safe Shutdown Earthquake(SSE) load conditions are carried out. Total 4 cases of different locations of the trolly and the hook are investigated. With the spring-damper element, the tension analysis of hoist rope is conducted. The stability of handling tool under earthquake load condition is conformed with regulatory guide.

• 한국공간구조학회논문집
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• 제19권4호
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• pp.35-44
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• 2019

Recently, the occurrence frequency of earthquake has increased in Korea, and many cultural assets have been damaged. Cheomseongdae is a valuable cultural assets that must be preserved historically and culturally. But, the masonry structure such as Chemseongdae is vulnerable to lateral forces. Therefore, in this study, structural modeling and dynamic analysis are performed to reflect the ground state and structural form of Cheomseongdae. Also, discrete element analysis technique is applied and dynamic behavior characteristics are analyzed according to earthquake load. For this purpose, displacements and stresses according to locations are reviewed and then swelling and distortion are analyzed.